/Engine/Source/Runtime/MovieScene/Public/MovieScene.h
RemoveTrack
[UMovieSceneTrack](API\Runtime\MovieScene\UMovieSceneTrack) * FindTrack ( [TSubclassOf](API\Runtime\CoreUObject\Templates\TSubclassOf)< [UMovieSceneTrack](API\Runtime\MovieScene\UMovieSceneTrack) > TrackClass ) const